This invention relates to vests for use in water, generally, and in particular to an improved flotation vest and harness arrangement. In one form, the vest is a buoyancy compensator particularly useful for skin and scuba diving, and in another embodiment, the flotation vest is a personal flotation device or PFD which is used by canoeists, rafters, etc. The principal difference between the two forms of the invention is that the former is inflatable and deflatable, while the latter is filled with a buoyant, foam material.
In the field of skin and scuba diving, particularly recreational scuba diving, flotation vests or devices have changed rather dramatically since they were first introduced more than 25 years ago. Initially, such devices were intended only for emergency flotation at the surface of a body of water. An early device was simply a slender, pleated tube which was inflated by a CO.sub.2 cartridge into a balloon shape when emergency flotation was needed. Soon thereafter, a Mae West vest was developed including an oral inflation tube and a small, CO.sub.2 cartridge; either could be used to inflate the vest but, again, this type of vest was designed primarily for emergency flotation.
Somewhat later, it was found that the Mae West type of vest just discussed could be used underwater to trim the diver's specific gravity to neutral buoyancy, at any selected depth. This was accomplished by removing the scuba regulator from the mouth and orally inflating the vest through the oral inflation tube, if the diver was too "heavy" or by releasing some air in the vest through the oral inflation tube if the diver was too "light". Used thusly, the Mae West type of vest became the first buoyancy compensator for divers, but, obviously, improvements were needed.
Later developments included a vest having a greater internal capacity or volume than the early Mae West vest, this later vest also being equipped with an enlarged oral inflation tube with a more comfortable and easily used mouthpiece and an enlarged capacity CO.sub.2 cartridge for emergency inflation at the surface or to raise the diver to the surface of a body of water. A significant development thereafter was to provide an inflation device connected to the oral inflation tube, the inflation device being connected by a tube to the tank of air being carried on the diver's back. Thus, buoyancy compensation or control beneath the water could be easily accomplished by simple manipulation of the inflation control without need of removing the scuba regulator from one's mouth followed by oral inflation of the vest.
Later developments lead to three basic types of buoyancy compensators and these reflect the present state of the art, prior to this invention. The first is a chest-mounted vest known in the art as a "horse collar" design, which may be used for scuba diving or skin diving (snorkeling). The other two devices are designed for scuba diving only. The first is a vest which is mounted on the backpack of a conventional scuba tank and backpack assembly and, when inflated, assumes the shape of an inverted "U". This type of vest has an advantage over the horse collar design, in that the diver's chest is free of a vest. However, the principal drawback of this design is that, when fully inflated, it will float a diver on the surface of a body of water in a stable, face down position; in an emergency, particularly if the diver is unconscious, the results could be fatal. A third type of flotation device currently used in scuba diving is a jacket-type of device which is rather permanently affixed to the backpack of a conventional scuba tank and backpack assembly. While satisfactory for scuba diving, the device is cumbersome and somewhat unsuitable for skin diving or snorkeling and, thus, is not used for this purpose.
The prior, patented art includes U.S. Pat. No. 3,269,129 issued to R. C. Zambrano which discloses an early scuba tank backpack including a crotch strap and a waist belt with a buckle. Later, scuba tank backpack developments include U.S. Pat. Nos. 3,174,664 issued to D. L. Hue and 3,957,183 issued to D. L. Gadberry. These latter two patents disclose scuba tank backpacks of the type commonly in use today, with a harness assembly including two shoulder straps and a waist belt with a buckle. The major drawback of this design is that the scuba diver wears a second, weight belt with a belt buckle. In an emergency, the scuba diver may wish to "ditch" the weight belt so as to return to the surface rapidly. However, with two belt buckles at the diver's waist, it can be very difficult to determine which one is the weight belt and which one is the belt holding the scuba tank in place.
An example of the horse collar-type of buoyancy compensator or vest above discussed is disclosed in U.S. Pat. No. 3,536,071 issued to J. V. Ferrando. The design is typical and includes a waist encircling strap with a crotch strap. While this type of vest is useful for both skin and scuba diving, the harness assembly including the waist strap and crotch strap is not at all satisfactory. Specifically, with this arrangement, the diver is free to move inside of the harness and the flotation bag of the vest can easily move out of position Thus, it may be difficult for the diver to control his attitude under water and, at the surface, the diver's head can actually be tilted forward to a stable, face-down position in the water. Obviously, this can be extremely dangerous. All front-mounted buoyancy compensators have this deficiency, and it centers about the center of buoyancy of such buoyancy compensators. A long moment arm of force is created because the diver's center of gravity is at the waist where the weight belt is located, and the center of buoyancy is at the diver's neck. Thus, a stable, vertical attitude with the diver's neck above the diver's waist can be assumed in the water, whereupon the face of the diver is forced downwardly into the water.
There are other difficulties with conventional, chest-mounted, horse collar buoyancy compensators. Since they are bulky, they create resistance when the diver attempts to swim. These devices have uncomfortable harnesses which allow the compensator to move about the diver's body. Such buoyancy compensators have a confusing array of straps and buckles which create unneeded bulk and can easily be confused with the scuba harness and weight belt. With the confusing arrangement of straps and buckles located at the diver's waist, it is very easy for the diver to release the wrong buckle when an attempt is made to ditch the weight belt in an emergency.
In direct contradistinction to the prior art as just discussed, the present invention is an improved flotation vest which is streamlined when compared to the prior art and includes a harness assembly with straps that will not be confused with other equipment worn by the diver, particularly the weight belt and the weight belt buckle. Essentially, the harness is a rather radically modified parachute type harness. Prior U.S. Pat. No. 3,475,774 issued to J. M. Hawkins discloses an inflatable vest and harness for marine life saving which is designed for use by personnel making parachute descents from aircraft. However, this device would be most unsuitable for skin or scuba diving because the harness assembly is far too complex and buoyancy is limited to the collar of the device, thus making underwater buoyancy compensation virtually impossible.
The instantly disclosed and claimed invention provides a streamlined buoyancy compensator which may be intregated with a scuba tank and backpack, if desired, and is extremely comfortable to wear. Uncomplicated and rapid access to the diver's weight belt is assured so that an emergency ascent to the surface, when needed, may be most easily accomplished. Equally importantly, the flotation vest of this invention, in the form of a buoyancy compensator, may be used alone for snorkeling or may be combined with an otherwise conventional scuba tank and backpack assembly for scuba diving. Additionally, another form of the invention is used for white water rafting, canoeing and the like. In this case, the vest is filled with foam material yet it remains comfortable to wear and is also streamlined in configuration.